[Intel-gfx] [PATCH 14/17] drm/i915: Add stats for GuC log buffer flush interrupts

[Tvrtko Ursulin]

On 10/07/16 14:41, akash.goel at intel.com wrote:
> From: Akash Goel <akash.goel at intel.com>
>
> GuC firmware sends an interrupt to flush the log buffer when it
> becomes half full. GuC firmware also tracks how many times the
> buffer overflowed.
> It would be useful to maintain a statistics of how many flush
> interrupts were received and for which type of log buffer,
> along with the overflow count of each buffer type.
> Augmented i915_log_info debugfs to report back these statistics.
>
> Signed-off-by: Akash Goel <akash.goel at intel.com>
> ---
>   drivers/gpu/drm/i915/i915_debugfs.c        | 26 ++++++++++++++++++++++++++
>   drivers/gpu/drm/i915/i915_guc_submission.c |  8 ++++++++
>   drivers/gpu/drm/i915/i915_irq.c            |  1 +
>   drivers/gpu/drm/i915/intel_guc.h           |  6 ++++++
>   4 files changed, 41 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
> index 3c9c7f7..888a18a 100644
> --- a/drivers/gpu/drm/i915/i915_debugfs.c
> +++ b/drivers/gpu/drm/i915/i915_debugfs.c
> @@ -2538,6 +2538,30 @@ static int i915_guc_load_status_info(struct seq_file *m, void *data)
>   	return 0;
>   }
>
> +static void i915_guc_log_info(struct seq_file *m,
> +				 struct drm_i915_private *dev_priv)
> +{
> +	struct intel_guc *guc = &dev_priv->guc;
> +
> +	seq_printf(m, "\nGuC logging stats:\n");
> +
> +	seq_printf(m, "\tISR:   flush count %10u, overflow count %8u\n",
> +		guc->log.flush_count[GUC_ISR_LOG_BUFFER],
> +		guc->log.total_overflow_count[GUC_ISR_LOG_BUFFER]);
> +
> +	seq_printf(m, "\tDPC:   flush count %10u, overflow count %8u\n",
> +		guc->log.flush_count[GUC_DPC_LOG_BUFFER],
> +		guc->log.total_overflow_count[GUC_DPC_LOG_BUFFER]);
> +
> +	seq_printf(m, "\tCRASH: flush count %10u, overflow count %8u\n",
> +		guc->log.flush_count[GUC_CRASH_DUMP_LOG_BUFFER],
> +		guc->log.total_overflow_count[GUC_CRASH_DUMP_LOG_BUFFER]);
> +
> +	seq_printf(m, "\tTotal flush interrupt count: %u\n",
> +			guc->log.flush_interrupt_count);
> +
> +}
> +
>   static void i915_guc_client_info(struct seq_file *m,
>   				 struct drm_i915_private *dev_priv,
>   				 struct i915_guc_client *client)
> @@ -2611,6 +2635,8 @@ static int i915_guc_info(struct seq_file *m, void *data)
>   	seq_printf(m, "\nGuC execbuf client @ %p:\n", guc.execbuf_client);
>   	i915_guc_client_info(m, dev_priv, &client);
>
> +	i915_guc_log_info(m, dev_priv);
> +
>   	/* Add more as required ... */
>
>   	return 0;
> diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c
> index c1e637f..9c94a43 100644
> --- a/drivers/gpu/drm/i915/i915_guc_submission.c
> +++ b/drivers/gpu/drm/i915/i915_guc_submission.c
> @@ -914,6 +914,14 @@ static void guc_read_update_log_buffer(struct drm_device *dev)
>   		log_buffer_state_local = *log_buffer_state;
>   		buffer_size = log_buffer_state_local.size;
>
> +		guc->log.flush_count[i] += log_buffer_state_local.flush_to_file;
> +		if (log_buffer_state_local.buffer_full_cnt !=
> +					guc->log.prev_overflow_count[i]) {
> +			guc->log.prev_overflow_count[i] =
> +					log_buffer_state_local.buffer_full_cnt;
> +			guc->log.total_overflow_count[i]++;

Is log_buffer_state_local.buffer_full_cnt guaranteed to be one here? Or 
you would need to increase total_overflow_count by its value?

> +		}
> +
>   		if (log_buffer_copy_state) {
>   			/* First copy the state structure */
>   			memcpy(log_buffer_copy_state, &log_buffer_state_local,
> diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
> index bdd7a67..c3fb67e 100644
> --- a/drivers/gpu/drm/i915/i915_irq.c
> +++ b/drivers/gpu/drm/i915/i915_irq.c
> @@ -1711,6 +1711,7 @@ static void gen9_guc_irq_handler(struct drm_i915_private *dev_priv, u32 gt_iir)
>   						&dev_priv->guc.events_work);
>   			}
>   		}
> +		dev_priv->guc.log.flush_interrupt_count++;
>   		spin_unlock(&dev_priv->irq_lock);
>   	}
>   }
> diff --git a/drivers/gpu/drm/i915/intel_guc.h b/drivers/gpu/drm/i915/intel_guc.h
> index 611f4a7..e911a32 100644
> --- a/drivers/gpu/drm/i915/intel_guc.h
> +++ b/drivers/gpu/drm/i915/intel_guc.h
> @@ -128,6 +128,12 @@ struct intel_guc_log {
>   	struct workqueue_struct *wq;
>   	void *buf_addr;
>   	struct rchan *relay_chan;
> +
> +	/* logging related stats */
> +	u32 flush_interrupt_count;
> +	u32 prev_overflow_count[GUC_MAX_LOG_BUFFER];
> +	u32 total_overflow_count[GUC_MAX_LOG_BUFFER];
> +	u32 flush_count[GUC_MAX_LOG_BUFFER];
>   };
>
>   struct intel_guc {
>

Regards,

Tvrtko